MS Access IsNull Function with Examples in SQL Query and VBA Code

Null is empty field that indicate the data is missing or unknown. IsNull function is the opposite of Is Not Null function. Normally, the attributes in field database are set to allow Null value except for Primary Key field.

The syntax for IsNull function is:

( expression ) IsNull

Parameter:

Expression: the required SQL statement for returning the result. The IsNull function is only valid for SQL.

The table above named Borrow Table in Library Database. You can see that the ReturnDate field has the null value, meaning that the book is still borrowed and has not returned yet. Meanwhile, we need to create a field named Status to display whether the book is returned or not.

Create a new query by going to Create tab > Queries group > Query Design.